2. Python Power Tip: Get File Extensions from Filenames
   Concepts:Python: A general-purpose, high-level programming language known for its readability and ease of use.Filename: The name assigned to a computer file
3. Transforming Text into Valid Filenames: A Python Guide
   Allowed Characters:Filenames can only contain specific characters depending on the operating system. Common allowed characters include alphanumeric characters (a-z, A-Z, 0-9), underscores (_), hyphens (-), and periods (.)